- function as or act like;
"This heap of stones will act as a barrier"
- pretend to have certain qualities or state of mind;
"He acted the idiot"
"She plays deaf when the news are bad"
- I must find someone to act as a deputy for me during my absence.
- He was appointed to act as the executor.
- Maybe I can act as a messenger for you.
- It is hoped that the tax cuts will act as a stimulant to further economic growth.
- A group of people gathered to plan or discuss an issue, judge a contest, or act as a team on a radio or television quiz program.
- The forest will act as a defense against desert dust.
- The dean of the school act as marshal of graduation ceremony.
- act as act like
乍然看来，act as和 act like是两个同义短语，在涵义上无甚区别可言，其实不然。
- act as:act as意思是“充当”、“担任”，相当于 serve as，可与人或物词如：doctor、director、interpreter、guide、coach、 teacher、go-between、furniture、tools等字搭配使用。as是连词，引导一个省略了谓语的状语从句。例：This herb can act as an antidote against snakebite．这种药草可以用作蛇咬的解毒药。
- Last summer she acted as a guide for tourists．
- This coin may act as a screwdriver．
- Mr．Liu acted as group leader while Mr．Zhang was ill．
- act like:act like意思是“行为像”、“举动像”，相当于英语的 to act in the manner of，它常与人或动物名词连用。like是介词，其后接宾语。
- That child acts like a grown-up．
- Don't act like a fool！
- 他拒绝了我们的建议，真使我们扫兴。（注：a wet blanket 作“令人扫兴的事或人”。）
- His refusal of our offer acted like a wet blanket．